Temperature Rise Rapid Prediction for High-Power Linear Ultrasonic Motors in High Vacuum

This paper presented an improved thermal network model for temperature rise rapid prediction of high-power linear ultrasonic motor (HPLUM) in high vacuum. The particularity of the heat conduction of piezoelectric materials is considered in the presented thermal circuit elements. The overall losses including mechanical damping losses and the three internal losses in piezoelectric elements, as well as the impact and friction losses occurring in the contact interface between the stator and the mover were calculated analytically. Then the calculated losses were used as the thermal sources inputted to the developed thermal network to predict the transient and steady-state temperature rise of the motor in high vacuum. Finally, the FEM-based temperature field analysis was conducted to validate the developed rapid thermal prediction model of HPLUM under high vacuum condition.